I used Wolfram Alpha to evaluate: [itex]lim tan[(2nπ)/(1 + 8n)][/itex] n->infinity it says that it can use the continuity of tan(n) at n = π / 4 to rewrite the aforementioned function as: [itex]tan[lim ((2nπ)/(1 + 8n))][/itex] n->infinity What is it talking about? I was taught to use certain properties of trig functions as they pertain to limits to solve limits of trig. functions, but this is a bit beyond me. P.S. I'm not using WA to do my homework or anything, I just wanted to see how one goes about solving a trig. limit like this, as I felt that it wasn't very straighforward.